Oxygen mask



FIG. 1 is a front and side perspective view of an oxygen mask, showing my new design;

FIG. 2 is a front elevational view of the oxygen mask of FIG. 1;

FIG. 3 is a back elevational view of the oxygen mask of FIG. 1;

FIG. 4 is a top plan view of the oxygen mask of FIG. 1;

FIG. 5 is a bottom plan view of the oxygen mask of FIG. 1;

FIG. 6 is a left elevational view of the oxygen mask of FIG. 1;

FIG. 7 is a right elevational view of the oxygen mask of FIG. 1; and,

FIG. 8 is a cross-sectional view of the oxygen mask of FIG. 1, taken in the direction of line 8-8 of FIG. 2.

The broken lines in the drawings illustrate portions of the oxygen mask that form no part of the claimed design. 

CLAIM The ornamental design for an oxygen mask, as shown and described. 